The invention relates to a method of producing a composite nonwoven for receiving and storing liquids or the like, comprising a carrier nonwoven which, to consolidate it, is e.g. hydraulically needled, and a pulp layer, such as a wood pulp layer, applied to the consolidated carrier nonwoven and brought into secure contact with same. A method of this type emerges from EP 0 540 041. There the carrier nonwoven is hydraulically needled, essentially not to consolidate it but in order to increase the permeability of the carrier nonwoven to liquid. To the carrier nonwoven needled in this way is then applied the super-absorbent pulp in a layer, and the two are brought into good bonding contact and then the composite nonwoven is dried.
It has become apparent that pure consolidation by compression only produces an insufficiently secure contact between the pulp and the carrier nonwoven. A satisfactory connection of the wood pulp fibres to the carrier nonwoven is known e.g. from U.S. Pat. No. 3,560,326 or WO 92/08834, specifically through hydraulic needling of the wood pulp fibres with the consolidated carrier nonwoven. This type of connection results in a high loss of pulp fibres however. Tests have shown that up to 12% of the wood pulp fibres are washed out of the useful layer or bond and are thus lost for the efficiency of the product. Moreover, in this process very many pulp fibres get into the filtration, necessary in the case of water needling, of the circulating water. Due to the additional increased outlay for the purification of the recycled water, the product also becomes more expensive. Water needling at only a low water pressure does not produce the necessary strength; or a stronger carrier nonwoven causes costs which are too high.